Textile treating apparatus



March 14, 1961 Filed March 29, 1960 g 20 I. J1

Sheets-Sheei'l 1 22 22 ya .-54 2a I 24 25 if i g L E f 0^ I' .72 ilu ii' il' il' 50 1 l |y I w( 40 :H l 1| I' g 'Il .75

48' 50' jg, 6.0/ .I- V 70 fw 5H 4 64 60/` Q INVENTOR lwzasl'arier /5 BY Mmz,

ATTORNEY March 14, 1961 E. P. CARTER 2,974,512

TEXTILE TREATING APPARATUS Filed March 29, 1960 5 Sheets-Sheet 2 IN VENTOR BY WMM/# ATTORNEY March 14, 1961 E. P. CARTER 2,974,512

' TEXTILE TREATING APPARATUS Filed March 29, 1960 5 Sheets-Sheet 3 M 56 i2 III 5 @a l 56 I 5f 6.0 1i 55 y a2 I I 55 I I I I I |Vv Y,

| IIII'HI.

Emest Zadel? ATTORNEY March 14, 1961 E. P. CARTER TEXTILE TREATING APPARATUS 5 Sheets-Sheet 4 Filed March 29, 1960 March 14, 1961 E. P. CARTER 2,974,512 TEXTILE TREATING APPARATUS Filed March 29, 1960 v l /75 /gg 'Jn/gay: (E Tia l il. #ms/72 INVENTOR Elzwtl? Lfter T f BY v mw ATTORNEY United States Patent O TEXTILE TREATING APPARATUS Ernest P. Carter, Decatur, Ala., assignor to The Chemstrand Corporation, Decatur, Ala., a corporation of Delaware Filed Mar. 29, 1960, Ser. No. 18,343

18 Claims. (Cl. 68-5) This invention relates to textile treating apparatus and more particularly to an apparatus for conditioning a tow of filamentary material lformed from a synthetic composition such as acrylic polymers or the like with a pressurized fiuid such as steam.

In the production of many synthetic filaments and particularly those of the acrylonitrile type, the polymer is spun by a wet spinning process into a plurality of continuous filaments which form what is generally termed a filamentary tow. During the subsequent processing of this continuous filamentary tow it is subjected to various conditioning operations, one of which involves attenuating or stretching the heated tow filaments so as to orient the molecules of the filaments and align them in the direction of the filament axis. Y

This stretching of the heated tow filament imparts certain highly desirable physical characteristics to the filaments, among which are high tensile strength and low denier. Although these stretched filaments possess lexcellent physical properties when formed into yarn and lfabric, they are prone to fibrillate or split off into fibrils when subjected to abrasion or other forms of strain. This fibrillation causes abraded portions of the fabric formed from these filaments to appear lighter in color than the remaining parts, thus giving the illusion of wear. It is thought that the fibrillation results from the internally strained condition of the molecular structure of the filament created during the stretching operation. In addition to this proneness to fibrillation inherent in the internally strained filaments, the stretched filaments also have a high residual shrinkage capacity and tend to shrink on subsequent -heating at elevated temperatures. Furthermore, as a result of the stretching operation, the filament extensibility is decreased, thus limiting the use of such filaments in textile operations such as knitting and weaving where a high extensibility is desired.

`It has been found in the past that the above discussed undesirable physical characteristics inherent in stretched filaments may be overcome or reduced by heating the internally strained filaments while they are in a relaxed condition. This heat-relaxing treatment, generally termed annealing has been found to reduce or substantially eliminate fibrillation while increasing extensibility and generally improving the quality of the filament. In one widely used method for carrying out this annealing operation, the tow is processed in a batch-type operation which involves loading large quantities of tow material into autoclaves or similar pressure vessels wherein it is subjected to steam under pressure for an extended period of time while in a relaxed condition. While this method of annealing lamentary material gives generally satisfactory results, it suffers several significant drawbacks. In the first place, it is well known that filaments formed from acrylic material such as acrylonitrile polymer tend to take on a yellow hue when subjected to elevated temperatures over an extended period of time.

This `so-called batch-type of annealing process is not,

ice

therefore, well adapted for producing a white end product, since `the large mass of filaments cools slowly and therefore remains in a heated state for longer periods than necessary for annealing purposes. As a result of such prolonged heating, the filaments tend to `discolor to such an extent that the white end product is difficult to obtain.

Moreover, this batch-type of annealing process is quite time consuming, since it requires the interruption of the substantially continuous operation involved in the manufacture of synthetic filamentary material while the large batches of vfilament are placed in the autoclave, brought up to proper pressure and temperature, cooled and then removed by hand for subsequent processing.

Furthermore, the batch-type proces-s is generally expensive from the standpoint of both time and labor expended, and particularly with regard to the initial investment and maintenance of large and bulky apparatus which requires considerable floor space.

In view of the above-discussed drawbacks to the 4batchtype process and because lamentary tow is produced in a continuous strip form, it has been suggested that a continuous type of annealing operation would be of exceptional advantage commercially, both from the standpoint of cost and of quality. However, continuous annealing of tow presents many problems as a result of such limiting factors as the high speed at which the tow is advanced in conventional equipment and the fact that the tow must be subjected to a high pressure fluid. When high pressure steam, for example, is the annealing medium, the tow must move continuously through a region of high pressure while in a relaxed condition so as to be contacted by the steam and permit the effective carrying out of the annealing operation. Maintaining this high pressure region in a substantially sealed state while the tow passes through the medium presents a serious structural limitation. While various devices have been suggested `for carrying out a continuous annealing operation none have proved completely satisfactory for one or more of a variety of reasons. Some have been of such complicated design and so costly to construct as to be impractical. Also, the need for many internal moving parts with close tolerances has led to frequent breakdown because of the corrosive effect of steam and water on the moving parts. Moreover, the requirement for large overall dimensions to accommodate these moving parts has been a deterrent.

A primary object of this invention is to provide a novel apparatus -for the treatment of textile material.

Another object of this invention is to provide an apparatus for annealing internally strained filamentary material in an intermittent manner which is both rapid and efficient. A further object of this invention is to provide such an apparatus for semi-continuously annealing a row of filamentary material formed from a synthetic composition such as acrylonitrile polymers and the like.

Another object of this invention is to provide a new and novel apparatus for annealing lamentary material formed from acrylonitrile polymers and the like which substantially eliminates the tendency of the filament to discolor, and consequently produces a relatively White annealed textile product.

A further object of this invention is to provide an apparatus for annealing filamentary material which subjects successive portions of the material to a pressurized fluid, maintaining a seal about the material and preventing the discharge of the pressurized fiuid from the apparatus into the surrounding atmosphere.

Still another object of this invention is to provide an apparatus for annealing tow by means of pressurized steam wherein said apparatus is simple in construction move the tow along the conditioning path in intermittent v steps.

The present invention provides an apparatus for annealing tow of filamentary material in an intermittent manner which generally includes a conditioning chamber having extensible ingress and egress ends on either side thereof. tensible ends and are adjustable from a normal tow release position to a gripping position. Means are provided to reciprocate these feeding means and to actuate them to gripping position in timed steps so that the tow is gripped and pulled through the chamber in the first stage of the moving cycle, whereupon the feeding means are released to allow movement of the feeding means in the opposite direction of reciprocation. The feeding means are then again actuated to gripping position and a new portion of tow moves with them in the first mentioned direction.

The above objects and other objects as wel'l as many of the attendant advantages of this invention -will be Feeding means are positioned adjacent the exreadily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which v t Figure 1 is :an elevational view of one embodiment of from is a guide shield 58. l

the invention shown partially broken away for clarity of illustration;

Figure 2 is an enlarged sectional view taken on line 2--2 of Figure 1 and partially broken away, illustrating the tow gripping elements of the feeding means of the apparatus shown in Fig. l;

Figure 3 is a fragmentary enlarged sectional view illustrating in more detail the valve means for closing the annealing chamber of the embodiment shown in Figure 1;

Figure 4 is a fragmentary sectional view taken along line 4-4 of Figure 3 showing an opening through which the tow advances into the annealing chamber;

Figure 5 is a fragmentary elevational view of a second embodiment of the invention shown partially vbroken away and illustrating a different type of tow gripping means; l

Figure 6 is an elevational view of a third embodiment' of the invention shown partially broken away for clarity of illustration wherein the apparatus is in position for the start-up of the annealing operation;

Figure 7 is an elevational view of the embodiment of Figure 6 showing the Iapparatus in position during the first step of the annealing operation;

Figure 8 is a fragmentary sectional view on an enlarged scale illustrating one of the tow gripping units and-surrounding structure of the apparatus illustrated in Figure 6; and

Figure 9 is a sectional view taken on line 9-9 of Figure 8 showing the opening in the tow vvgripping vunit through which the tow is advanced. l

Referring now to the drawings, and particularly Figures 1 and 3 thereof, reference numeral 10 indicates an annealing chamber which contains a steam inlet conduit 12 terminating in a baie 14. The baie, of course, is provided so that high pressure steam entering the chamber will be more evenly distributed therethrough without turbulence and resulting entanglement of the iilavided a condensate exhaust 16 which has associated therewith a conventional steam trap (not shown) to prevent escape of steam and consequent reduction of pressure within the chamber 10. Reference numeral 18 indicates a pressure Agauge at the top of the chamber.

Within the chamber is positioned a tow guide 20 around which a tow line 22 is passed in relaxed condition from the ingress to the egress of the chamber.

Drawing attention now to the upper left hand portion of the drawing of Figure 1, reference numeral 24 indicates a double-acting air cylinder which is rigidly alixed to a frame 26 of the apparatus. Mounted for reciprocation within this cylinder is a hollow shaft 28. Reference numerals 30 and 32 indicate the air conduits for introduction of air into the upper and lower portions of the cylinder 244. A piston 34 integral with the hollow vshaft 28 urges the shaft downward upon the entrance of air through lthe conduit 30 and upward upon the en- Aportion to accommodate two concavely recessed portions `42 and 44.'

Reference numerals 46 and 48 indicate inflatable sealing and gripping I'tubes which are shown in their expanded form to lill the area within the enlarged portions of the connecting pipe 40 and compress the tow line Z2 passing between the tubes. Reference numerals 50 and 52 denote the position that the tubes occupy in their uninfiated state, which is illustrated by a dotted line showing. Reference numeral 54 denotes an air conduit for the introduction and withdrawal of air to inflate and deflate the tubes 46 and 48. Attached to the enlarged central portions of the connecting pipe 40 and descending there- Beneath the enlarged central portions 42 and 44, th connecting pipe 40 is threadedly joined to a bellows 60. The bellows 60 is threadedly engaged at its lower end to a pipe 62 which communicates with the annealing chamber 10.

Reference numeral 64 denotes a ap valve which maintains steam pressure within the lannealing chamber 10,

and which is designed to fall into open position except when the pressure beneath the valve exceeds the pressure above the valve and forces the valve into a closed posi- `tion as shown. In other words, when there is no pressure differential above and below the valve, the valve will fall open. Forming a part of the valve is small steam vent 66 (Figures 3 and 4). Reference numeral 68 j denotes an exhaust vent conduit having a valve 70 therein.

This valve 70 communicates with an enclosed area (not shown) which is at atmospheric pressure to avoid escape of the steam into the atmospheer around the apparatus.

All of the portions of the apparatus on the left hand side of the annealing chamber which are designated by reference numerals 24 through 70 comprise the tow feeding and chamber sealing means. These parts nd'their exact counterparts in the tow withdrawing and chamber sealing means on the right side of the Iannealing chamber. Therefore, to avoid needless repetition, the equivalent parts of the structure to the right of the annealing chamber have been given the same numerals prime. In

`other words, reference numerals 24 through 70 are equivalent tothe parts indicated by reference numerals 24 through 70. It will be noted that the bellows 60 'is shown expanded while the equivalent bellows 60' is shown compressed.

-Referring now to Figure 2 of the drawing, which illustrates a sectional view through the enlarged central portion of the connecting pipe 40, the inflatable sealing tubes 46 land 48 are shown joined with air tubes 72 and 74 j which are fed by the air inlet tube 54 previously mentioned for inllation and deflation of the sealing tubes.

Various means can be employed to actuate the above `as such, no particular structure has been shown.

With regard to the operation of cylinders 24 and 24 a satisfactory means which has been employed is to provide a conventional source of pressurized fluid which is passed by way of a two-way Valve to either of conduits 30 or 32 for reciprocation of the piston 34 and the hollow shaft 28 within the cylinder 24. A conventional timer may be provided to signal a servomechanism which in turn actuates the two-way valve. A similar arrangement is, of course, provided with regard to the actuation of the cylinder 24 and for the inflation of the tubes 46 and 48. The vent valves 70 and 70 may also be actuated by servomechanisms operated by a timer.

Before reciting a detailed description of the embodiment of the invention illustrated in the remaining igures of the drawing, the operation of the embodiment shown in Figures 1 through 4 will first be described.

With regard to the embodiment of the invention disolosed in Figures l through 4, attention is particularly directed to Figure l. In the start-up, the tow line 22 comprising a plurality of synthetic filaments, such as acrylonitrile polymer which has been previously stretched to orient the molecules, is passed from a supply source (not shown) down throughl the hollow shaft 28 through the connecting pipe 40 between the niiatable tubes 46 and 48 which are in an uninflated position (Figure 2) to allow the passage of the tow therethrough and down into the annealing chamber as shown.

The tow line 22 is then passed around the tow guide 20 and thence up through the open ap valve 64 through the open inatable tubes 46" and 48 and thence upward through the hollow shaft 28' to a suitable take-up means (not shown) As illustrated, sulcient tow is placed within lthe chamber 10 so that it is in a relaxed condition to permit shrinkage of the tow during the annealing operation. Steam from la conventional source is then passed under pressure through the conduit 12 into the annealing chamber 10 until the required pressure has been established as indicated by the pressure gauge 18. Generally, a quantity of supersaturated steam under a pressure of 40 p.s.i.g. is utilized for acrylonitrile ilamentary material.

With piston 34 in the up position as shown, the sealing tubes y46 and 48 are inflated to grip the tow line therebetween and form a seal between the lhollow shaft and the bellows section 60. At the same time the piston 34 is in the down position, thus compressing bellows 60r as shown, while inflatable tubes 46 and 48 are inilated to grip the tow therebetween and seal the passage. At this time bot-h of the exhaust vent valves 70 and 70 are closed, thus defining a confined passage between the inflated tubes '46 and 48, and 46' and 48. f As 4the steam pressure builds upwithin the annealing chamber 10 steam will be vented through the steam vents 66 and 66 to equalize the pressure above and below the flap Valves 64 and V64', thereby allowing the flap valve to fall open. rl`1l'1e piston 34 is now actuated in the downward direction to urge the inflated tubes 146 and 48 gripping the tow therebetween downward, and dropping the tow through the now open flap valve 64 into the chamber 10. Either simultaneously with the `downward movement of the pis ton 34 `or immediately thereafter, the piston 34 rises to lift the 'sealing tubes 46 and l48 to pull the tow line upward through the opened ilap` valve 64'.

At this point both of the exhaust vent valves 70 and 70' are opened, whereupon steam escapes from the area above the flap valves reducing the pressure therein. With the pressure in the steam chamber now greater than that above the flap valves, the valves 64 and 64 are forced closed. At this point, the sealing tubes 46 and 48 are deated and the piste-n 34 is moved upward. With 'the ap valve 64 holding the tow line 22, the tubes i V46 and 48 will move upward along the tow line for the distance of the cylinder stroke where they will be ready for the next cycle.

Similarly on the withdrawal or right hand side of the apparatus when the exhaust vent valve 70 is opened and the pressure above the flap valve thereby reduced, the ap valve `64 is forced closed. At this time the sealing tubes I46 and 48 are deflated and forced downward along the tow with the downward stroke of the piston 34. The

tow line 22 above the inatable tubes 46 and 48' is held` by the take-up source (not shown) so that the tubes 46 and 48 will move downward along the tow line.

The exhaust vent valves '70and 70 remain open only for an instant. After they close, the tubes 46, 48, 46' and 48 are again iniated, steam again escapes through the vents 66 and 66' to the areas above the ap valves, the pressure equalizes on each side of the flap valves, the valves therefore drop open, and the pistons 34 and 34 are 'moved to advance another section of tow 22 through the annealing chamber 10j. This operation may be controlled in any one of various well known manners.

Referring now tol-ligure 5 of the drawing, there is illustrated a second embodiment of the invention which is quite similar in structure to that embodiment shown in Figure 1, but differing in that ilap valves are employed as the tow gripping means instead of using iniiatable tubes as was the case in the embodiment of Figure 1. In View of the fact that rnost of the structure of this embodiment is identical to the structure illustrated in Figure l the same reference numerals have been used to designate the same parts to avoid confusion and repetitions description. A

On the left hand side Iof Figure 5 it will be noted 'that the hollow shaft 28 is joined by coupling joints 3S toa connecting pipe which is indicated by reference numeral 80. The connecting pipe has an enlarged central por tion 82, and is joined at its bottom portion to the bellows 60.

Within the enlarged central portion 82 there is provided a flap valve 83 made up of two lips 84 and 86 of a resilient, exible material. The valve is shown in open position with the tow line 22 passing therethrough.

Similarly on the right hand side of the drawing,` the hollow shaft 28' joins through the coupling joint 38' to a connecting pipe 80. 'Ilhis connecting pipe has an enlarged central portion 82 which is joined at its lower end to the bellows 60. Within the enlarged central portion 82 is located a flap valve 83' comprising lips 86 and 84'. 'Ilhe valve is shown in closed position with the tow line 22 `gripped therebetween.

.The operation of the embodiment of the invention illustrated in Figure 5 of the drawing is quite similar to that described with regard to the embodiment of Figure l.` In the start-up position, the piston 34 is at the upper part of the cylinder 24 while the exhaust vent valve 70 is open, thereby permitting communication to the atmosphere both above and below the Iflap valve 83, whereupon this valve will fall open. At the same time, the exhaust vent valve 70' on the right hand side of the chamber 10 is also open, thereby permitting the flap valve 83 to fall open and the tow line 22 to be passed downward through the Ihollow .shaft 28 into the annealing chamber and up through the pipe 62', the connecting pipe '40', and the hollow shaft 28 to take up or collecting means v(not shown).

Steam under pressure is introduced into the annealing chamber 10 while the exhaust vents 70 and 70' .are closed. As pressure is built up wit-hin the annealing chamber 10, steam escapes through the vents 66 and 66 to equalize the pressure above and below the ap valvesy 64 and 64. These ilap valves, previously held closed by the greater pressure below them, will now fall open, whereas the flap valves 83` and 83 will be `forced closed by the greater pressure below them, With the liap valves 83 and 83' being closed and gripping the tow line 22 therebetween, the piston 34 is lowered so thatA the -tow line is pulled downward into the annealing chamber through the open ap valve 64, and the piston 34' rises while the -ap valve 83 grips the tow line to pull the tow out of the chamber through the open flap valve 64'.

After the movement of the ilap valve 83 and the tow line 22 downward, the exhaust vent valve 70 is momentarily opened to bring the pressure in the area between the two flap valves to atmospheric conditions. The ap valve 64 will thereby be closed by the higher pressure within the annealing chamber 410 while the ap valve 83 will yfall open due to the equal pressures on either side of it. At this time the piston will be raised so that the llap valve 83 will move along the tow line 22 as the valve 83 travels in an upward direction before again gripping the tow for the next cycle. j

During this cycle, the exhaust vent valve 70' has been opened to equalize the pressure above and below the flap valve y83 while allowing the ap valve 64 to be forced closed by the pressure. within the annealing chamber 10. .The piston 34 then moves downward, pushing the flap valve 83 with it along the tow line 22 to its bottom position whereupon the exhaust vent valve 70 is closed, steam is again exhausted through the stem vent 66 and the cycle previously described is repeated.

Referring now to the third embodiment of the invention, which is disclosed in Figures 6 through 9 of the drawing, reference numeral 110 indicates a conditioning chamber which is surrounded by an insulating jacket 112. Reference numeral 114 indicates a steam inlet port, while the condensate exhaust port, provided with a conventional steam trap (not shown) at the bottom of the chamber, is denoted by reference numeral 116.

To the left ofthe conditioning chamber and tightly lengaging the end thereof is a metal bellows 118. This bellows is rthreadedly connected to a sealing and tow lgripping unit 120. The sealing and gripping unit 120 is coupled at its top portion to a hydraulic cylinder 122 through a piston rod 123, and is similarly joined at its bottom portion to a hydraulic cylinder 124 through a piston rod 125. The small circular elements 126 and i 127 on the face of the sealing and gripping unit are air tube conduits for actuation of the sealing and gripping unit in a manner which will be described later in connection with Figures 8 and 9 of the drawing.

To the left of sealing and gripping unit 120 and threadedly engaging the same is lanother metal bellows 128 which is joined to a connecting metal sleeve 1'29. sleeve =129 is rigidly anchored to the machine frame (not shown) ,to prevent movement thereof with the compression and extension of the bellows on either side thereof. Reference numerals :130 and 131 indicate check valves placed on the connecting sleeve 129 to allow the exhausting of steam. Vacuum exhaust means of a wellknown type (not shown) communicate with these valves.

To the left of the connecting sleeve 129 is a third metal bellows 132 which threadedly engages on its opposite side a second sealing and gripping unit 133. This unit 133 is coupledl at its upper end to a cylinder 134 `through a piston rod 135, and at its lower end to a i cylinder 136 through a piston rod l137. Reference numerals 138 and 139 indicate air tubes entering the sealing and gripping unit.

Referring now to the lright side of conditioning chamber 110, there is seen an identical arrangement of parts as vv:just described with regard to the lcft end of the chamber.

Reference numeral 140 indicates -a metal bellows joined to a sealing and gripping unit 141. This unit 141 is con- I nected to a hydraulic cylinder 142 through a piston rod l' 143 at its upper end, and to a cylinder 144 through a piston rod 145 at its lower end. Reference numerals 146 and `147 indicate air tubes entering the sealing and grippingunit 141. Connected to the opposite side of the unit r141 va metalbellows 148 joined to a connecting sleeve 14,9 provided'with'check valves 150 and 151 to permit-` l'the exhausting of steam. 'As stated with regard to valves' 8 130 and 131, vacuum exhaust means of a well-known type (not shown) are provided for the rapid withdrawal of steam, and prevention of steam escaping to the atmosphere.

The sleeve 149 joins another metal bellows 152 which threadedly engages a fourth sealing and gripping unit 153. This unit 153 is coupled to a hydraulic cylinder 154 through piston rod 155, and 'to a hydraulic cylinder 156 through a piston rod 157 for reciprocal axial movement of said unit. Reference numerals 158 and 159 denote air tubes entering the unit 153.

Reference numeral 160 indicates la tow iilamentary materiaL which is shown partially in dotted line, passing are provided at the end of the annealing train.

Drawing attention now to Figures 8 and 9 of the drawing, wherein a more detailed illustration of the sealing and lgripping units of the invention is shown, reference numerals 161 and 162 indicate the laterally-projecting, threaded shoulders of the sealing and gripping unit 120 which engage the metal bellows 118 and 128 on each side of the unit. Reference numeral 164 indicates the central bore passing through the unit and communicating with the passage of the metal bellows. In the center of the unit there are provided concave recessed portions 166 and 168 within which are positioned inatable tubes 170 and 172. Upon inflation these tubes expand to the positions indicated by the dotted lines 174 and 176, thereby compressing the tow line 160 between the tubes while closing the space 164 to form a tight seal. The sealing unit shown in Figures 8 andv 9 is joined to piston rods 123 and 12S which are journaled within the projecting ilanges 178 and 180 of the unit.

In the apparatus illustrated in the drawing, means are, of course, provided for inflation of the tubes within the sealing and gripping units, as well `as for actuation of the cylinders which move the units axially. Though no spemeans may be employed to inflate and deflate the tubes within the sealing and gripping units as Well as to reciprocate the pistons with-in the cylinders.

For ya description of the operation of the embodiment of the invention illustrated, attention is directed to Figures 6 and 7 of the drawings. At the start-up of the operation, the tow line 160 has been passed from the feed source through the apparatus and to the take-up means. At this point, the units 133 and 141 are closed, as indicated in Figure 6 of the drawing. The tow line passing through is thus held by the units 133 and 141 which :also form a sealed passage between those tow units. Steam is then introduced into the annealing chamber under the desired pressure which lls the area between units 133 and 141. The units 120 and 153 are open. As illustrated, the cylinders 134 and 136, and 154 and 156, are extended, while the cylinders 122 and 124, and 142 and 144, are closed.

The first cycle of operation is illustrated in Figure 7 of the drawing, wherein it is shown that closed units 133 and 141 have been moved to the right by the closing of the cylinders 134 and 136 and the opening of the cylinders 142 and 144. At the same time the open units and 153 have moved to the left by the action of the associated cylinders. In moving to the right, the closed units 133 and 141 pull the tow 160 `along therewith, since these units have formed a tight seal about the tow, while the open units 1120 and 153 merely slide along the tow as these units move to ward the left.

In thev next sequential step of operation, the units 120 and 153 close to form a sealed steam passage between those two units, while at the same time being moved to the right by the opening of the cylinders 154 and 156 and the closing of the cylinders 122 and 124. The units 133 and 1'41 yare open during this time, and are moved to the left, sliding across the tow, by the opening of the cylinders 134 and 136 and the closing of the cylinders 142 and 144. While the steam is sealed between the units 1'20 and k153 that quantity of steam which remains in the passage between the now closed unit 120 and the open unit 133 is quickly drawn oft" by vacuum means (not shown) through the actuation of Ithe valves 130 and 131. This, of course, prevents the escape of steam to the surrounding atmosphere lthrough the open unit 133. The desired steam pressure is maintained through continual lintroduction of steam to compensate for 'any loss.

The units 133 and 141, which are now once more in the position shown in Figure 6 of the drawing, again are closed to form la tight seal about the tow 160 passing therethrough so that the steam is now sealed within the passage between the units 133 and 141. The valves 150 and 151 in the connecting sleeve 149 are now actuated to quickly withdraw the steam present in this section of the passage to prevent escape of steam to the atmosphere through the now open unit 153i. Again units 133 'and 141in closed position are moved to the right by the associated cylinders while the open units 120 and 153` are moved to the left by the associated cylinders. The cycle described above is then repeated so that the lamentary tow 160 is intermittently moved through a sealed steam region.

To summarize the operation brietiiy, it is seen that sealing and gripping units 133 and 141 act together to move the tow `160 toward the right while the sealing and gripping units 120 and 153 are open and moveto the left. The units 133 and 141 then open and move to the left while the units 160 and 153 close about the tow line and move to the right therewith.

To allow for shrinking of the filament-ary tow during the annealing step the tow line is not stretched tautly within the annealing passage at the start-up, but rather in a loose fashion to allow for a certain amount of shrinkage. This relaxed state of the tow within the annealing passage is maintained by the subsequent movement or advancement of the tow by the sealing and gripping units.

It can be seen that with the novel construction of the invention, nlamentary tow or any other similar material may be continuously subjected to a pressurized fluid medium such as steam. The apparatus of the invention is particularly suitable for treating wet spun acrylic tow and permits such a tow to be eliiciently heat-relaxed or annealed in a simple and easy manner. The annealing operation is completely automatic and the novel construction of the invention permits control of the annealing conditions over a wide range in accordance with type of tow processed. Another of the outstanding features of the invention is that the escape of steam to the atmosphere about the annealing station is prevented, while means may be provided to positively remove said steam and enable the annealing conditions within the chamber to be accurately maintained at a predetermined level. The tow is smoothly and rapidly moved through the annealing chamber with a minimum of change in form so that contamination of the tow is prevented and anneatled tow of high quality emerges from the chamber at the completion of the operation.

It should be understood, of course, that the foregoing disclosure relates to only preferred embodiments of the invention and, that numerous modifications or alterations may be made therein without departing from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

1. An apparatus for `annealing Continous tow of filamentary material comprising an annealing chamber having extensible tow ingress and egress ends, means to introduce steam into said chamber, tow advancing means adja- 10 cent to the tow ingress and egress ends, said means being movable from Aa normal tow release position to a gripping position, means to reciprocate said advancing means, means to actuate one of said advancing means to gripping position in its movement toward said chamber and means to yactuate the other of said advancing means to gripping position in its movement away from said chamber, and means to prevent the `escape of steam along the tow path when the advancing means are in tow release position.

2. The apparatus of claim 1 wherein said means to prevent the escape of steam are positioned between said advancing means and said chamber.

3. The apparatus of claim 1 wherein said means to prevent the escape of steam are positioned beyond said advancing means.

V4. An apparatus for annealing continuous tow of lilarnentary material, comprising an annealing chamber, means for introducing steam into said chamber, means defining a tow entrance passage to said chamber and a tow exit passage from said chamber, said passage defining means having extensible portions, tow advancing means adjacent to said extensible portions and communicating with said passages, said advancing means being adjustable from a normal tow release to a gripping position, reciprocating means connected to the tow advancing means, means to actuate one of said advancing means to gripping position in its movement toward said chamber and means to actuate the other of said advancing means to gripping position in its movement away from said chamber, and means for preventing the escape of steam from said passages when the advancing means are in tow release position.

5. An apparatus for annealing continuous tow of ilamentary material, comprising an annealing chamber, means defining a tow entrance passage to said chamber and a tow exit passage from said chamber, said passage delining means having extensible portions, means for introducing steam into said chamber, means mounted within said passages adjacent to said extensible portions and adjustable from a normal tow release position to a tow gripping and passage sealing position, means to reciprocate said adjustable means along the axes of said passages, means to actuate one of said adjustable means to gripping and sealing position in its movement toward said chamber and means to actuate the other of said Iadjustable means to gripping and sealing position in its movement away from said chamber, and means to prevent the escape of steam along the tow path when the Iadjustable means are in tow release position.

6. The apparatus of claim 5 wherein said means to prevent the escape of steam are positioned between said adjustable means and said chamber.

7. The apparatus of claim 6 wherein said means to prevent the escape of steam comprise nap Valves at the passage ports of said chamber.

8. The apparatus of claim 5 wherein said means to prevent the escape of steam are positioned along said passages beyond said adjustable means.

9. The apparatus of claim 8 wherein said means to prevent the escape of steam comprise additional means which are adjustable from a normal tow release position to a tow gripping and passage-sealing position, and means to actuate said additional adjustable means to tow gripping and passage-sealing position when said just mentioned adjustable means are in tow release position.

lO. The apparatus of claim 5 wherein said adjustable means include inflatable tubes, and said actuating means include means to inllate said tubes to tow gripping and passage-sealing position.

11. The apparatus of claim 5 wherein said adjustable means include ap valves, and said actuating means includes means to regulate gas pressure on either of said ap valves.

12. An apparatus for annealing continuous tow of ',1'1 'iilamentary material including two pairs of tow advancing means, each pair deiiningv an aligned extensible tow path therebetween, one of each pair lying between the other pair, means to introduce steam into said path, means to actuate each of said tow advancing means from a tow gripping and path sealing position to a tow releasing and path unsealing position, means to move one pair of said advancing means in one direction when they are in gripping and sealing position while moving the other pairV in the opposite direction when they are in tow release and unsealing position.

. 13. An apparatus for annealing continuous tow of tilamentary material including an annealing chamber, means to introduce steam into said chamber, means deiining a tow entrance passage to said chamber and a tow exit passage from said chamber, said passage dening emans having extensible portions therein, two pairs of means within said passages adjacent to the extensible portions and adjustable from a normal tow release position to a tow gripping and passage sealing position, one of each pair lying between the other pair, means to reciprocate each pair of said adjustable means along the axes of said passages in an out-of-phase relation, and means to actuate one pair of said adjustable means to tow gripping and passage sealing position when the other is in tow i release position.

-tothe chamber, iirst sealing means mounted at the junction of the bellows and the chamber for gripping the tow and sealing the chamber to prevent the escape of said treating gas therefrom, second sealing means secured to the bellows at the other end thereof for gripping the tow and sealing said other end to prevent the escape of gas 1'2 therefrom, and means connected to said other end of the bellows for moving the second sealing means toward and away from the rst sealing means.

lr6.l A device for advancing a tow into a chamber containing a treating gas, comprising a bellows secured at one end to the chamber and communicating with said chamber, means mounted at said one end of the bellows `for gripping the tow and sealing the chamber to prevent the escape of gas therefrom, a pair of inflatable elements mounted at the other end of the bellows for cooperating to grip the tow and seal said other end to prevent the escape of gas therefrom, and means connected to said other end of the bellows for reciprocating said other end.

17. A device for advancing a tow from an area at one pressure level to an area at a different pressure level, comprising a bellows interconnecting said areas, rst means at one endof the bellows for gripping the tow and preventing the passage of the pressure medium, second means at the other end of the bellows for gripping the tow and preventing the passage of said pressure medium, and means connected to the other end of the bellows for reciprocating said other end.

18. A device for continuously annealing a tow, comprising a chamber containing steam for annealing the tow and having an opening for receiving the tow, a ap valve mounted at said opening for gripping the tow and preventing the escape of steam from the chamber, a bellows secured at one end to the chamber and communicating .with said opening, a pair of inilatable tubes mounted at the other end of the bellows for cooperating to grip the tow and seal said other end of the bellows to prevent the escape of steam therethrough, a tubular member secured to said other end of the bellows and communicating therewith for the passage of the tow, a uid cylinder having a piston secured to the tubular member for reciprocating said other end of the bellows, and means for venting the bellows.

No references cited.

UNITED STATES PATENT OFFICE CERTIFICATION UF QORRECTION Patent No,` 2,974,512 March 14I 1961 Ernest 1% Garter It is hereby certified that error' appears in the above numbered patent requiring colreetioh and that the said Letters Patent should read as corrected below'.

Column 4, line 54, for -"vatmospheerf"" read atmosphere W5 column 7, line 23, for ""stem' read steam --MV column 8,I line 12 ,l after lHim/vf insert -fof -.-;v column 11,L line 17 3L for ."emans" read -vmeans f.

Signed and sealed this 15th day of August 1961a (SEAL) Attest:

ERNEST W. SWIDER I DAVID L. LADD Attesting Officer Commissioner of Patents 

